Chapter V: Appendix: To Lesson XIII

ON THE USE OF THE SAW.

(_By John J. Holtzapffel._)

The steel buhl saw-frame (Fig. 16) may be very usefully employed for removing many of the superfluous portions of the material in the earliest stages of carving in the round, as in large or small figurini, and for those parts which have to be cut away to leave the outlines or margins between leaves and other ornaments in flat works. In such cases it is to be recommended, for its use not only saves much time, but also the risk of breakages, to which the work is very liable when these portions have to be removed entirely with the carving-tool.

In round carving, the block, more or less roughly marked out on its surfaces to some approach to its ultimate form with thick pencil or crayon lines, may be held on the work-bench by the carver's screw (Fig. 10), or if that be not convenient, or if it be flat work, it can be held in the vice. A coarse strong buhl saw-blade is employed; this is first fixed in the screw jaw at the further side of the saw-frame; the handle of the latter is then unscrewed until it projects its jaw about half-an-inch, and at the moment the other end of the blade is fixed therein, the two jaws are also made to approach one another by pressing the further side of the saw-frame against the work-bench, with the handle against the workman's chest; after this, the handle is screwed back again until its jaw returns home to its former position. The back of the saw-blade is towards the back of the saw-frame, and the teeth of the blade should point away from the handle, easily discovered by passing the finger along them, and when the saw is properly strained for use it should ring like a harp string.

In use, the handle of the frame is grasped by all the fingers of the hand, except the forefinger, which is stretched straight out along it in the direction of the saw; the latter is pushed straight forward and withdrawn with moderate pressure, just sufficient to cause it to cut, and is twisted about to follow the directions of the lines or curves of the piece to be removed. During the sawing the outstretched forefinger is an unerring guide for the direction of the cut.

When a piece has to be removed from between others which have to be left, as between the body and the bend of the arm, or between the legs of a figure, a small hole is first drilled through the block and the saw threaded through it before it is strained; and the only necessary precaution throughout in using the saw, is to leave sufficient material everywhere for perfect freedom in the subsequent carving by not cutting anywhere too close.

An entirely different method is followed in cutting out moulds, the pieces to be used for _appliqué_ carving, and for the outlines of fretwork or panels pierced with many interstices of which the surface is afterwards to be carved. These works cannot be held fast in the vice or otherwise, not only because they are often thin and liable to fracture, but because, if so held, it is impossible to attain the desired true, easy-flowing outlines required at once without subsequent correction, which can be produced without difficulty when the work is perfectly free.

The professional hand fret-cutter, who produces the best and most elaborate work, such objects as the long, thin, pierced panels to be backed with silk for the fronts of pianofortes, uses a similar, but much deeper, yet light saw-frame made of wood, with the same steel screw-jaws, hung to the ceiling by a cord. He sits astride a bench called "a horse," which has two tall vertical jaws in front of him, their upper edges lined with brass, or sometimes with cork. The further jaw is fixed to withstand the thrust of the saw, the other is notched below and springs open when left to itself, but is closed by a diagonal strut resting loosely in mortises made in the face of the bench and in that of the movable jaw; the strut is pulled downwards to close the jaw on the work by means of a cord passing from it through a hole in the bench to a treadle beneath the workman's foot. The surfaces of his work are, therefore, vertical, and the work itself is very lightly held, so that he can twist it about in all directions with the left hand, while he keeps the saw steadily traversing backwards and forwards in the same plane horizontally, with the right.

A simpler support, called a "saw table," Fig. 7 _b_, is used, and thoroughly answers every purpose for the smaller class of works which we are considering. This tool consists of an oblong piece of wood, perfectly flat, smooth and polished on its upper surface, at the one end of which there is a slot of about an inch wide; beneath, it has a cross piece of wood to keep the implement steady on the bench or table on which it is placed, and a clamp and screw to fix it there.

The work, first pierced with the holes for threading the saw through all its intended interstices, has the saw placed through one of them, strained as before, and is then laid down, pattern uppermost, on the saw table, upon which it is lightly held and twisted about by the points of all five fingers of the left hand planted vertically upon it; the saw is worked up and down vertically in the slot by the right hand, the handle below the saw table. The aim here is to keep the saw working always in the same place, and to let the curve or line result from the perfectly free movement of the work alone. The saw-blades employed are much finer than those previously referred to; they are tightly strained in the same way as before, but they are placed in the frame so that the teeth now point the reverse way, towards the handle, and the cut, therefore, takes place at the downward stroke.

The saws in ordinary use, such as the brass-backed tenon and dove-tail saws and the key-hole saws of the carpenter, also find constant employment in first roughly shaping and preparing the blocks and panels to be subsequently carved; in their use it is only necessary, as in all sawing upon carved works, to cut just sufficiently wide of the lines marked to ensure that all saw-marks will be removed by the carving tool.

FOURTEENTH LESSON.

INCISED, INTAGLIO, OR SUNK CARVING.

Deep carving, as it is termed by certain writers, is now known among artists as incised, sunk, or intaglio. It is an advanced form of gouge-cutting.

It is a very beautiful yet easy kind of work, which was extensively practised in Italy in early times, and which is deserving special attention because of its applicability not only to bold, large, and even coarse decoration--which was, however, very effective--but to the most delicate and minute objects. "It may," says General Seaton, who was the first to describe it, which he does with much enthusiasm, "be called sunk carving, for, contrary to the usual method, the carving is sunk, while the ground is left at its original level." Like engraving on metal, it cuts into the ground, and depends entirely on outline, or drawing, and shadow for its effects. It is suitable for book-covers, or to be employed wherever the carving is liable to be handled or rubbed, because, being sunk beneath the ground, it cannot be rubbed or injured till the ground itself is worn down.

Take any wood except a coarse one,--holly, beech, oak, poplar, pear, or walnut,--and let the surface be well planed, or perhaps polished. If it be a wood of light colour, draw your pattern with a very soft pencil, say _B B B_, on paper, lay it face down on the wood, and rub the back carefully with an ivory or other polisher. The work is chiefly executed with bent gouges and grainers, flat and hollow, with two or three bent chisels and stamps, and it often happens that a good piece of incised carving can be executed with very few tools. It is executed almost entirely by hand, or without hammering.

Choose some simple pattern, your object being to learn how to cut and not to produce something startling at a first effort. If the wood be dark, such as American walnut, mark the pattern through with the prick-wheel or dot, Fig. 54. If the pupil has not perfect eyesight, or expects to carve at night, it is advisable to outline this dot line with a very fine camel's hair brush and Chinese white. This prevents many mistakes. Take, to begin, a small gouge, a little less than the stem to be cut in diameter, and run it along the line. When you cut leaves, get gradually towards the centre. Then take a larger gouge and finish the stems.

Keep by you a piece of clay or putty, or moist kneaded bread, and from time to time take an impression of your work. This is important, for the real excellence of intaglio carving consists in its being exactly like relief carving reversed. In this way you will at once perceive, without any special directions, what tools to use in your work.

Fig. 55 is a rather advanced example of this class of carving. The whole of the foliage is cut in cavo relievo, or cavities, with gouges and chisels, both straight and bent, and the lines upon them with bent V tools. The duck in the centre may be in ordinary low relief, to give an effective contrast.

There is another reason for thus learning to make your work perfect. If you carve in hard wood, you can always use a piece of sunk or intaglio carving for a mould. When it is finished take a piece of russet leather, soak it in water till it is quite soft, press it with your fingers and a sponge for some time with great care into the mould, and then take it off. If your wood be well cut, the leather when dry will be quite as attractive as the carving itself, and may be used in many ways. The wood will not be injured in the least if you wipe it dry after taking the impression. With such moulds _papier-maché_ casts can also be taken. I have now before me a beautiful specimen of old Byzantine work made in this manner.

There is a peculiar kind of intaglio carving which may be called Egyptian, because the ancient Egyptians used it very extensively on their monuments. It consisted of cutting out the outline of a figure in the following manner. On the _outside_ the carver cut down perpendicularly, while the inside pattern was not cut away, but only had its edges rounded.

The result of this peculiar groove or cut, straight on one side and rounded or curved on the other, was a very strong relief and shadow. It was in fact a simple combination of relief and incised or cavo carving, by means of which a strong relief was attained by little work. The main object was to make the inscription solid and durable, and at the same time very legible. The principle, as I have shown, is quite applicable to ornament, and requires much less labour than even intaglio carving. It is something more, in fact much more, than mere outlining, and it is particularly applicable to mural or wall decoration.

Incised carving is often much improved by being painted, and sometimes varnished. That is to say, the sunken portion is thus coloured. I have seen white and vermilion used with good effect, but black and dark brown are generally preferred. Gilding seems peculiarly rich when thus applied in the hollow, as the shadow gives it a fine tone.

Though the imitation of engravings is not within the range of wood-carving, there is, however, a very pretty and easy art by which drawing and painting are very ingeniously combined with a kind of carving. Take a panel of firm wood of lightish colour, well planed and polished. Draw on it any pattern, or even an animal, or human figures. Incise the principal lines with a V tool, or, according to its size, small gouges may be used. For the fine lines and shading, a tracer, or any point to indent, not so sharp as to scratch; this is a matter of great importance; and the wood, which, if possible, should be of box, sycamore, beech, or holly, must be adapted or prepared to take a mark without breaking. When all the lines are well in, take a miniature fitch pencil, and fill in every line with colour, taking care not to let the paint spread beyond the lines. Different colours may be used. This is hardly wood-carving at all, but in skilful hands it produces beautiful and remarkable effects. It is very effective indeed when applied to leather. As the colour is _sunk_ in the lines, it is well protected; this kind of ornamentation is therefore well adapted to book-covers. I have applied it successfully to heavy card-board panels prepared for artists to paint on in oil.

As I have said, incised cutting will be found useful to workers in leather, papier-maché, clay, or plaster of Paris, because by means of it they can make moulds. Another kind of mould is made as follows: Cut out with a saw the outline of the pattern in a piece of board thick enough to give the requisite depth. Then glue the perforated board to another board, the surfaces of both being of course first planed and smoothed. This gives the mould in the rough. Then fill in the angles of the hollows with a composition of clay and size, or putty, or rice and lime with white of egg, or any other suitable cement, and while it is soft shape it with fingers and tools to the details of the pattern required. When perfectly dry go over it carefully, taking proofs here and there with putty, and correct with bent files. Then smooth it where it is at all rough, oil it all, and make your cast.

FIFTEENTH LESSON.

CARVING CURVED SURFACES: COCOA-NUTS, BOWLS, HORNS, CASKS, TANKARDS, ETC.

Carving concave or convex surfaces, such as the exterior of a horn or the interior of a bowl, is often very difficult work, and though an ingenious artist will readily find out for himself some way to get over such difficulties, it is well to know at once how the work may be done.

HORNS. The first difficulty is to fix the object so as to cut it. A beginner who undertakes to carve such a very hard, slippery, and unmanageable object as a horn, will, if he hold it with one hand while he carves with the other, inevitably damage his pattern or wound himself. It is very dangerous to hold the work in one hand or between the knees. One way to secure such an object is to take a board, nail cross-pieces on it over the ends of the horn so that a portion may be exposed on which to work, and in this manner one can cut with safety. Again, holdfasts and clamps may be employed, but the utmost care should be taken lest these slip away whenever too great pressure is brought to bear on them. A very good means to keep the horn firm is to have a piece of wood fast to the table in which there is a hole, into which the lesser end of the horn fits, while the butt rests, and is fixed, on the table. Having secured it, outline the pattern with a V tool or very small graining-gouge, and then cut away the ground with quarter-flat, and finally with flat gouges. The bent file may be freely used for a horn, and it will be necessary in many places. When bosted, finish with careful touching or fine files and glass-paper.

If you wish to colour the horn, select one which is chiefly white. Take a solution of nitrate of silver, which any chemist will prepare for you. Be very careful indeed how you handle it, for it will burn clothes, carpets, or flesh, and at least stain your fingers for a long time. With a _glass brush_, if you can get one, if not, with a glass point, or pen, or agate point, or wax, apply the acid carefully to the pattern. If you use wood for this purpose it will answer, but it is very speedily consumed by the acid. This will make a yellow, or brown, or sometimes a black stain, according to the strength of the solution, the number of times it is applied, and the hardness of the horn. When the horn is covered with diaper-work, or a great many small figures, or a close pattern, then always put the acid into the hollows, and leave the design in white. A black dye for horn, as well as for metal, is made by combining ammonia with sulphur. It is very malodorous, but is effective. Any chemist will make it, and will also prepare for you the dyes used for ivory and horn. It is better and cheaper for the amateur to buy these than to attempt to make them for himself. In most cases black and brown are the best colours to use.

If a horn is boiled in hot water, or steamed, it will become so soft that it may be flattened. Then it is very easy to carve. The author has in his possession two very ancient and singularly ornamented Italian horns which were thus shaped. Horn, when treated with quick-lime and hot water, can be reduced to a paste which can be made into any shape like a cement or plaster. It becomes hard again in cold water. All old horns were not used for gunpowder; many of them were for wine or other liquors; others were used for blowing; they all make effective ornaments. Carved horns are handsome ornaments when hung up with cord and tassels. I have made them very attractive by gilding the raised patterns on them.

TO CARVE A BOWL. The exterior of a bowl presents no special difficulty, if it be well clamped down. It may be secured with blocks and nails, or screws. But the _interior_ is harder to get at and much harder to cut. This is, of course, chiefly done with bent gouges and chisels. It requires care and patience in cases of special trouble. I have, however, easily succeeded in wearing or wasting away the ground by the process which will be described in carving cocoa-nuts. Wooden bowls, which are well adapted to carving, may be bought cheaply at household furnishing shops. They are of the kind used in every kitchen. They may be mounted on bases, such as any turner can make, to which the bowl should be fastened with a screw and glue. Bowls may be coloured or gilded like horns. They are very useful for many purposes, chiefly to contain visitors' cards or other small objects on the writing, work, or toilet table.

COCOA-NUTS. If it is to be used as a cup, begin by sawing away the end on which is the "monkey face," or so much as is desirable. Sometimes the whole nut is left, to be hung up as an amulet, ornament, or charm, as ostrich eggs are hung up in the East. Then clean it smooth with a large rasp till fit to carve. Draw the pattern on this with Chinese white, that there may be no mistakes. Then fix the nut to the board or table, as with the bowl (_vide_ p. 100).

The ground may, with patience, be cut away with flat gouges, and, with practice, this becomes really easy, and more expeditious than one would at first suppose. Or it may be done chiefly with files. But the most rapid manner of working is by a "cut" which is described as follows by Gen. Seaton, who, however, limits it to mere decoration for a ground.

"There is a species of ornament most useful for the bend of branches, and which is to be seen in Swiss carved brackets. This may be called the _zigzag_ pattern or ornament. It is intended to represent the cross-fissures and marks that are seen in the bark of some trees at the end of the branches. It is done with a flat or quarter-round gouge, the hand swaying from side to side, and at the same time advancing by alternate steps each corner of the tool."

That is to say, put the tool straight up and down, and _rock_ it from side to side, and it will require little practice to learn it. But to use it, not for ornament, but a cut, or rather dig, a _firmer_ or chisel is better than a gouge; nor need we be very particular as to the appearance of the marks made, as they are all, in the end, to be cut or smoothed out. Rock up and down with the firmer, pressing a little flatter than if the object were to only make lines, or so as to scrape away some of the ground. Then from another direction go over this ground, digging and scraping away again. In this manner a shell may be bosted rapidly, and by it one can work at the bottom of a bowl when even the bent tools are of little or no use. When the whole ground is excavated by this process it may be easily smoothed with files or carving tools. The cuttings from cocoa-nut shell, or waste bits, may be kept, and when pounded to a fine powder, and mixed with glue, they make an admirable cement for repairing walnut or other dark wood work.

CASKS. A cask when carved is an admirable object for waste-papers, or holding canes and umbrellas, Fig. 56. It should be of wood at least one inch in thickness. If held together by broad brass or copper hoops it will be much handsomer. A bucket or pail may be carved in like manner; and when lions' heads or other carved ornaments are _applied_, it will be found that a very ornamental object may be made with little trouble or expense. It is easiest to carve casks, kegs, buckets, or firkins, up and down, or in a perpendicular position, and to stand up while at the work, as a true carver is sure in the end to do at all his work.

TANKARDS AND WASTE-PAPER BOXES. Tankards, if small, may be turned from solid wood, but, when large, it is best to have them made by the cooper, of several pieces, and hooped with metal. To make the design for all such cylindrical objects, take a piece of paper which will _exactly_ go round, or correspond to the surface, and be sure to make the pattern continuous, that is, without breaks, unless it be designed in divisions. Wooden measures, such as are used by dealers in nuts, fruit, etc., are well adapted to carving for tankards. They may be bought at general furnishing shops.

OLD IRISH TANKARD.]

The old Irish, and sometimes the Danes, made a rude kind of tankard, Fig. 58, by fastening together with nails, glue, or screws, four pieces of oak panel or thin board. It was like drinking from a box. It makes a useful receptacle for many purposes.

SIXTEENTH LESSON.

BOSSES, KNOBS, BARS, AND POLISHED ORNAMENTS.

There are several small effects in ornament which the carver should study with care; they are generally applicable to most kinds of decorative art. The first of these is the employment of bosses or knobs, some left plain, and some carved, hemi-spherical or less. They may be almost flat, but are always smooth at the edge and polished. They were very extensively used in early carving and metal-work, and the reader may see many illustrations of them in the works of Hulme. Sometimes the knob becomes a small spot or a mere dot, employed to introduce light into a dark ground. The practical theory is that the knob represents the plain or ornamental head of a nail used to hold the work to the wall, or the rivets of armour, which the Goths transferred from coats of mail to linen and woollen. But the real reason is to introduce points of light.

Knobs or bosses may be placed wherever there are wide spaces between patterns. The rule of employing them is either a few large points or many small ones; they must, however, be used sparingly. The principle of introducing them is of very wide extension. Thus, in all kinds of work, especially metal, grapes, melons, and other fruit are introduced solely that, by their roundness and polish, they may make points of light or "shiners." Old embossed work in leather and wood-carving often owes its chief beauty to the polish, which time and use have given to the reliefs on it. Of course the employment of "shiners" or bosses, and of all kinds of smooth polished relief, should, as a general rule, be sparing, subordinate, and judicious.

Nevertheless, in certain kinds of work, especially in much flat-carving, which is intended to simply ornament a surface, at no great expenditure of labour, just as tiles or tapestry might do, the stems and portions of the leaves, or sometimes all the pattern, may be polished as highly as possible, so as to make a relief against the dark ground. Grounds are pricked or punched or dotted to make them dark, and when the oil soaks into the holes they become permanently darker. Therefore the pattern is to be in contrast; and when the object is no more than to make a general decorative effect, not perfectly finished, but like a sketch, it may be polished.

There is another curious effect given by crossing the pattern alone, or the ground alone, with bars, lines, or stripes. It was very common at one time. In carving, it may be produced with a small gouge or fluter; though not natural, except where it is given in long and short lines to represent the graining of wood, it has a good effect simply because it distributes shadow evenly. It was probably derived from the effect of "ribs" in cloths, which were much admired by the Venetian painters.

Door-knobs are effectively bosses, that is to say, the same ornamentation may be applied to both, as to handles for bureaus, cabinets, and other furniture. Figs. 59 to 62 will give the pupil some examples and ideas for carving knobs and bosses.

SEVENTEENTH LESSON.

TO REPAIR WOOD-CARVING--GLUE--NITRIC ACID GLUE--PREPARING DECAYED WOOD--ARTIFICIAL WOOD--FILLERS--SPRAYING--TO MAKE GLUE "TAKE."

It will sometimes happen to a carver that, owing to bad wood or inadvertence, he splits away or breaks off a piece from his work. In this case he must have recourse to glue. This should be of the very best quality, perfectly light and clean. Glue is made in what alchemists used to call a _balneum mariæ_, that is, of a vessel containing hot water, within which is a smaller vessel. The glue, which is in the inner pot, is therefore to be boiled by the heat of warm water, and not of the fire directly. Before setting it to boil, break it into very small pieces, say of the size of a hazel nut, and let it stand in cold water for twelve hours. It will now be like a thick jelly. Pour off all the water not absorbed, and put the jelly into the inner pot, fill the outer with water and let it boil till the glue is like a thick cream. Use it while in this state.

If you add to the glue, while thus liquid, some nitric acid, say about a tea-spoonful to half a pint of glue, you will have a very superior cement, which holds faster than the plain glue, and is much less liable to crack or split. It dries more slowly, which makes it very valuable for veneering and for large surfaces, where glue often dries before the whole can be applied. Again, when an article fastened with common glue is detached, it is often almost impossible to stick it on again with the same. But with the acidulated glue this is easy.

The greatest advantage of this glue is, that if it be kept excluded from the air it will remain in a liquid state for at least a year, and can be used cold. Its disadvantages are a very pungent and not agreeable smell, and the fact that, when corked up, the cork is most certain to get glued to the bottle, and requires to be broken to get it out, rendering a new one necessary. This may be avoided, however, with great care. Stir the acid into the glue with a glass rod or tube.

It may happen that a rotten, broken place is found even in the best wood; or the carver may obtain possession of a piece of ancient, worm-eaten, half-decayed carving, and with a very little skill such pieces can be perfectly repaired. Take a piece of similar wood, and reduce it to fine sawdust by means of a rasp. For this purpose American walnut and dark old oak, or cocoa-nut shell, which is easily pulverized in a mortar, is excellent. Make this into a paste with glue, and repair with it any broken places. This, if properly made, is quite like wood itself, and may be moulded into any shape. It "takes hold" of the ground, and when dry it may be filed into uniformity with the rest. It may also be cut with ease or trimmed to shape, or, in fact, carved. If there is too little glue in it it will break too easily, if there is too much it will be too glazy. But a proper mixture makes it quite like wood.

Scratches and chance cuts may be remedied by merely melting them with hot water. But for such small defects a _filler_ is useful. This is a kind of paint or liquid cement, the object of which is to fill up the pores of certain coarse woods and make the surface fine. The squeezing wax, described in the chapter on making moulds, is a filler. Others are made by mixing flour with varnish, etc. Any dealer in paints and varnishes will supply a filler suitable to any special work.

When a piece of wood-work is so decayed that it is absolutely dropping to pieces, and cannot even be handled, it may be preserved and rehabilitated by the following process. Take some thin glue and water, or mucilage, or size of any kind, and a _spray_, that is, one of those articles such as are used for spraying perfumes, etc., and which are for sale in most chemist's shops. Spray or sprinkle the glue over the figure, and, if necessary, gradually throw on it fine sawdust or other powder. As it dries it may be shaped and worked more freely.

We read continually in the newspapers of the opening of old tombs and ancient subterranean caves, in which are discovered dead bodies, bones, dresses, implements of bone and wood or leather, or even of baked earth, which gradually dropped into dust a few hours after being exposed to the air. And I have never known a case in which these objects could not have been preserved; certainly all which I have ever seen could have been. All that is necessary to do is to make a thin size, and very gradually spraying or sprinkling it on the objects, allow it to dry, little by little. There are very few cases in which, indeed, the spray cannot be successfully used. It was by the application of this principle that Sir Joseph Hooker preserved the ivory articles brought from Nineveh by Sir Austen H. Layard, and which would have perished but for him. He advised that they should be boiled in gelatine. The student who becomes an expert in such repairing will find plenty to do, and it will be his own fault if it is not profitable. Nineteen people out of twenty have not the least conception of the degree to which repairs may be carried. Some years ago a gentleman in America had a very curious and valuable vase from the pyramid of Cholula in Mexico. It was very fragile, being made of the weakest terra-cotta, and having been broken to pieces, the owner was about to throw it away, but gave it to me. Some months after I repaired it so perfectly that the closest observation could not detect a flaw in it. I did this by fastening pieces of paper on the inside with gum, and so gradually bringing the fragments together, edge to edge, and fastening them with the acidulated glue. When all were together, there was, of course, a lining of paper. Where there was a fault or a deficiency outside, I filled it in with plaster of Paris, rubbed it all even, and coloured by "rubbing in" paint. This process would have been much easier with decayed wood.

In gluing ordinary wood together, heat the two pieces first. This renders them more inclined to "take" the glue. Sometimes it is a difficult thing to hold them together till they "set," that is, adhere so firmly that they will hold. For this the clamp, Fig. 7_a_, may often be used. In other cases, take two pieces of wood, put one on each side of the parts to be glued, and tie them tightly together; sometimes clamps may be used to connect the binding pieces, when they are not applicable to what is to be glued. Strong indiarubber rings or gummed paper strips may be used in some cases. But with thought, ingenuity can generally be awakened so as to help one out of any such difficulty.

A very perfect resemblance to carved wood may be made by taking cocoa-nut powder or fine sawdust and mixing it with the acidulated glue, so as to make a paste as already described. Then, having ready a mould, either of plaster of Paris or of sunk or incised wood, and oiling it, take the impression. These casts, retouched and glass-papered, are quite like wood, and they may be used for decoration in doors.

The following are also excellent recipes for glue.

_Liquid glue._ Take of best glue three parts, place them in eight parts of water, allow them to soak for some hours. Take half a part of hydrochloric acid (muriatic acid), three-quarters of a part of sulphate of zinc, add to these the glue, and keep the whole at a moderately high temperature till fluid.

_Exceedingly strong cement_ for glass and china. Take gum arabic and dissolve it in acetic acid instead of water. It must be melted in a hottish place; it will be much stronger if this be done. The finest quality of sheet gelatine makes a transparent glue.

EIGHTEENTH LESSON.

COLOURING WOOD-WORK--OILING--SODA--STAINS AND DYES--IVORYING SURFACES--BLACK DYES AND INK.

Carved or any other wood is often dyed, stained, or toned. Sometimes this is done to make one piece or part match with another; or it may be to imitate the effect of age, or to give light woods a colour which will prevent them from showing defects. This is effected in many ways.

_Oiling_ alone is a kind of colouring, for all oiled wood becomes much darker before long. The more frequently it is rubbed in with a pine stick the harder and darker the surface becomes. I have seen walnut tables which had been thus rubbed with a stick or a hard scrubbing brush, until a tea-cup wet with hot water on the outside would make no mark on them. Had they been only softly oiled or painted, or varnished, an indelible stain must have resulted. Care should be taken that the oil is pure, and that _no wax_ has been boiled in it. A table which has had wax on it for a polish will always show marks or stains from hot water.

_Soda_ dissolved in water, and applied to oak with a sponge or brush, will give it a darker tone, which may be increased by several applications. Dark tea with a little alum is also useful, also porter or beer, also a decoction of walnut leaves. In America butternut gives a very rich indelible dye. Let it be carefully observed that in using these, or any other colours, the following rules must be strictly observed. I. Use a sponge or brush and do not apply the dye profusely or pour it on, as you will run great risk of warping the wood, or causing it to split. II. It may be advisable to dry it near a fire, but in this case exercise great care that the heat be not too great. III. When dry, rub the dye off with a rag or soft old newspaper, or chamois skin. Do this very carefully, and do not be disappointed if it seem very light and to have taken but little dye. Apply the dye again, giving it plenty of time to dry between the coatings. Of course this depends on the dyes used, and the degree of colour required.

_Stephens' stains_ of different kinds, to imitate all kinds of wood, or those of _Mander_ (Oxford Street, London), are very good, and may now be purchased in every town. As a rule, most of these dyes are very strong, and it is therefore necessary to dilute them with water and make several applications, instead of putting on the whole strength at once. The diluted dye is carefully painted over the entire surface with a full flat camel's hair brush, and a smaller round brush is used in the corners and smaller recesses. After using dyes, and when perfectly dry, the wood should be oiled.

_Ammonia._ Wood, and especially oak, may be not only stained of a very dark rich colour, giving the effect of age, by washing it carefully with ammonia or spirits of hartshorn, and then exposing it for some time in a chimney, or otherwise to the fumes of smoke, especially of a wood-fire if it be possible. Strong spirits of ammonia, according to Rowe, may be placed in an open vessel and then shut up with the panel in an airtight chamber or box, the wood darkening according to the length of time it is left in. The ammonia may have to be renewed, as it quickly evaporates. For small work a glass shade may be used, or a box can be made with a glass lid, and after the panel and saucer of ammonia have been placed inside, the crevices can be pasted over with brown paper. When the depth of colour is obtained, which can be seen through the glass, the panel can be taken out. The wood must be so placed that the ammonia can pass quite round the parts which require darkening. But for ordinary purposes, it will be found quite sufficient to apply strong ammonia with a brush or sponge, and expose it to smoke.

_Umber._ Common powdered umber, which is used by the house painter, is much preferable to the Swiss brown liquid stain to produce an antique brown appearance. The Swiss dye is entirely too rich and uniform, making everything exactly alike, or similar to chocolate. But the umber must be properly applied. Mix it with beer or porter; strong coffee is also very good; and apply it with a brush. When dry rub it very carefully, clean, and apply it again. If it be desirable to make the wood very dark, add lamp-black to the dye, mixing and shaking it very thoroughly. But always let the first applications be of umber alone. By adding the lamp-black one can darken the wood almost to blackness, and if it be very carefully done, and not in a hurry, and exposed at intervals to smoke in a warm place, a colour second to none may be thus given.

_Paint._ Wood which is to be exposed to the air must of course be painted in the ordinary way. But there is another method of applying oil paint which is not so generally known or practised, yet which gives very good results. This consists of _rubbing_ paint with the hand into wood or on plaster of Paris, papier-maché, or stone. As it is much thinner than with coats laid on with a brush, it appears more like an innate or natural colour. This was the finger painting of the old Venetian artists. The appearance thus produced, when it is skilfully done, is very different indeed from that of an ordinary coat of paint, and in most cases it is much more attractive.

_Ivorying._ Take a panel, the pattern may be carved, or even produced in the lowest relief by simply indenting the outline with a wheel or tracer. Any degree of relief will, however, do just as well. Apply a coat of thick ordinary copal varnish. When perfectly dry smooth it with finest glass or emery-paper. Then apply the paint; two or three coats are better than one. See that the last is perfectly smooth. Then work on the dry surface with tracer and stamps, as you would on wood or brass. When finished, take a very small fitch-brush and paint Vandyke brown into all the dots, lines, scratches, and irregularities. Let there be a dark line of brown close to the outline of the pattern. Sometimes the entire ground may be _rubbed_ with brown, allowing an indication or a few dots of white yellow to show here and there. When dry give two coats of retouching varnish (that of Söhnee Frères, No. 19, Rue des Filles du Calvaire, Paris, is specially suited to this work). By using olive, dark and light greens, a beautiful imitation of bronze can be thus obtained. In fact, by studying the effects of colour in many kinds of old objects, we may obtain hints for converting very ordinary wood-carving into beautiful objects.

_Bichromate of Potash_, diluted with water to the required shade, is a good dark dye, but great care should be taken not to spill a drop of it on the clothing, or to get it on the hands, or even to inhale its fumes, as it is a poison. Apply it with a brush.

_Black Dyes._ Of late years black dyes have been so much improved that ebony is imitated with holly, hickory, and beech, to absolute perfection. The best way for the carver, as regards these and all kinds of dyes, such as red, yellow, green, etc., is to go to a chemist or colourman, who will obtain them for him. For black the following recipes may be used.